The present application claims the benefit of and priority to a pending provisional application entitled “Over-Voltage Protected Class E Converter,” Ser. No. 61/635,664 filed on Apr. 19, 2012. The disclosure in this pending provisional application is hereby incorporated fully by reference into the present application. The present application also claims the benefit of and priority to a pending provisional application entitled “Over-Voltage Protected Class E Power Converter,” Ser. No. 61/652,091 filed on May 25, 2012. The disclosure in this pending provisional application is also hereby incorporated fully by reference into the present application.
I. Definitions
As used herein, the phrase “group III-V” refers to a compound semiconductor that includes a group V element and at least one group III element. Moreover, the phrase “III-Nitride” or “III-N” refers to a compound semiconductor that includes nitrogen (N) and at least one group III element, including aluminum (Al), gallium (Ga), indium (In), and boron (B), and including but not limited to any of its alloys, such as aluminum gallium nitride (AlxGa(1-x)N), indium gallium nitride (InyGa(1-y)N), aluminum indium gallium nitride (AlxInyGa(1-x-y)N), gallium arsenide phosphide nitride (GaAsaPbN(1-a-b)), and aluminum indium gallium arsenide phosphide nitride (AlxInyGa(1-x-y)AsaPbN(1-a-b)), for example. III-Nitride also refers generally to any polarity including but not limited to Ga-polar, N-polar, semi-polar or non-polar crystal orientations. A III-Nitride material may also include either the Wurtzitic, Zincblende, or mixed polytypes, and may include single-crystal, monocrystalline, polycrystalline, or amorphous structures. Gallium nitride or GaN, as used herein, refers to a III-Nitride compound semiconductor wherein the group III element or elements include some or a substantial amount of gallium, but may also include other group III elements in addition to gallium.
Also as used herein, the phrase “group IV” refers to a semiconductor that includes at least one group IV element including silicon (Si), germanium (Ge), and carbon (C), and may also include compound semiconductors SiGe and silicon carbide (SiC), amongst others. Group IV also refers to semiconductor materials which consist of layers of group IV elements or doping of group IV elements to produce a strained group IV material, and also includes group IV based composite substrates including silicon-on-insulator (SOI) substrates, silicon-on-sapphire (SOS) substrates, and separation by implantation of oxygen (SIMOX) substrates, amongst others.
II. Background Art
Power converters, such as class-E power converters, are utilized in a variety of high and low voltage applications. For example, because class-E power converters offer high efficiency, generate small switching losses, and typically display relative immunity to component tolerances, they may be utilized as power converters in induction heating (IH) and lighting applications.
Due to the advantages described above, IH cooktops utilizing class-E power converters enjoy considerable popularity. However, conventional class-E power converters are designed for use with stable power sources, which may not be consistently available everywhere IH cooktops utilizing class-E power converters are presently in use. For example, voltage transients can cause mains power to fluctuate substantially from nominal values, exposing the power switch or switches typically implemented as part of a class-E power converter to over-voltage induced damage or failure.